St. Peter's Church is called "ad Muricentum" or "ad Centum murum", due to the presence of numerous Roman remains that characterize it. The church was built in the thirteenth century on the ruins of the villa of Marcus Agrippa. The pavement reconstruction works, in fact, brought to light a number of areas, re-used over time as ossuaries, which belonged to the Roman villa recognised by an inscription as the "Baths of Agrippa". In the church many materials from the Roman era were reused, the villa walls were destroyed only in part, and Roman paving resurfaced, parts of frescoed walls, and a perfectly plastered cistern that give an idea of the majesty of the building. The facade of the church is gabled with an asymmetrical roof and the interior has two aisles. Near the church is the Romanesque bell tower with a square plan with two rows of mullioned windows. The church, although altered over time, retains the features of the original Romanesque structure. The interior decorations and important pictorial cycles go back to the end of the fourteenth century and the first half of the fifteenth century.